In a certain research laboratory, some yttrium-90 has leaked into the computer analysts's coffee room. The leak will presently expose personnel to 80millirems of radiation a day. The half life of the substance is about 5days; I.e the radiation level is only half of what it was five days ago. The analyst wants to know how long it will be before the radiation is down to a safe level of 0.855millirem a day.
Write a program in c that will create a chart that displays the radiation level for every five days with the message unsafe or safe accordingly. The chart should stop before the radiation level is one-tenth of the safe level, because the analyst requires a safety factor of 10. The program should prompt the user to enter the initial radiation level.

Long question, simple question... What do u want us to do with the question? Make we dey praise u say ur school hard? Just joking sha

Brb although I don't know C. This problem is interesting.

Its a very simple questions, u just got scared by d size..
_______
-
printf("enter initial radiation level" ;
float rad, tmprad; int days=0;
scanf("%f", &rad);
tmprad = rad; //to avoid false positive in the while condition
float tok = 0.855
,safelevel = (1/10) * tok; // one-tenth the safe level
while(tmprad > safelevel){
if(tmprad/2 > safelevel)//forward checking
{ printf("current radiation level is %f, safe level of %f will be achieved in %d days time", tmprad, tmprad/2, days+5);
break;
}
printf("at day %d, radiation level is %f => unsafe!\n", days, tmprad);
tmprad = tmprad/2;
days += 5;
}
-----
____________

Quite simple, NO BIG DEAL, Stop the hype, its what you have been taught

Not trying to hype . Though we've been taught some basics. Buh dis waz kinda tricky... Jez seeking solution here datz all.

after working on @mobolaji88 code

#include <stdio.h>
const int HALF_LIFE = 5;
const float RAD_SAFE_LEVEL = 0.855;
const float SAFTY_FACTOR = 0.10;
#define RAD_SAFTY_FACTOR_LEVEL SAFTY_FACTOR * RAD_SAFE_LEVEL
int main(){
	float initialRadLevel,tmpRadLevel;
	int days = 0;

	printf("Enter initial Radiation Level: ";
	scanf("%f", &initialRadLevel);

	tmpRadLevel = initialRadLevel;
	printf("Initial Radiation Level is : %f\n", initialRadLevel);
	while(tmpRadLevel > RAD_SAFTY_FACTOR_LEVEL){
		tmpRadLevel /= 2;
		days += HALF_LIFE;

		if (tmpRadLevel <= RAD_SAFTY_FACTOR_LEVEL)
		{
			printf("The current safe Radiation Level of %f will be achieved in %d days time.\n", tmpRadLevel, days);
			break;
		}

		printf("at day %d, Radiation Level is %f => unsafe !!\n", days, tmpRadLevel);
	}
}

jacob05:
after working on @mobolaji88 code

#include <stdio.h>
const int HALF_LIFE = 5;
const float RAD_SAFE_LEVEL = 0.855;
const float SAFTY_FACTOR = 0.10;
#define RAD_SAFTY_FACTOR_LEVEL SAFTY_FACTOR * RAD_SAFE_LEVEL
int main(){
	float initialRadLevel,tmpRadLevel;
	int days = 0;

	printf("Enter initial Radiation Level: ";
	scanf("%f", &initialRadLevel);

	tmpRadLevel = initialRadLevel;
	printf("Initial Radiation Level is : %f\n", initialRadLevel);
	while(tmpRadLevel > RAD_SAFTY_FACTOR_LEVEL){
		tmpRadLevel /= 2;
		days += HALF_LIFE;

		if (tmpRadLevel <= RAD_SAFTY_FACTOR_LEVEL)
		{
			printf("The current safe Radiation Level of %f will be achieved in %d days time.\n", tmpRadLevel, days);
			break;
		}

		printf("at day %d, Radiation Level is %f => unsafe !!\n", days, tmpRadLevel);
	}
}

I think we have a correct answer! You should allign your code well, its difficult to parse