Pls help.

2men and 7 boys can do a piece of working 4 days. it is done by 4 men and 4 boys in 3 days how long would it take for 1man or one boy to do it alone

Apatient is given 50 mg dose of medicine the medicines effectiveness decreases every hour at a constant rate of 40% what is the exponential decay function that models this scenario how much medicine will be left in the patients system after 2 hours

Mrs. gehrke said cheddar weighs 16.8 pounds. he actually weighs 15.2 pounds. what is the percent error?