Please help me answer all the questions:

Question 1:

\f\f(1 point) The voltage V across a charged capacitor is given by V(t) = 630-5' where t is in seconds. (a) What is the voltage after 5 seconds? 0.29872241 volts (round to the nearest 0.001 volts) help (numbers) (b) When will the voltage be 1? In C] seconds (round to the nearest 0.01 sec.) help (numbers) (c) By what percent does the voltage decrease each second? -45.11 % (round to the nearest 0.001%) help (numbers) (1 point) Students in a fifth-grade class were given an exam. During the next 2 years, the same students were retested several times. The average score was given by the model f(t) = 82 1610g10(t+ 1), 0 $15 24 where I is the time in months. (a) What is the average score on the original exam? (b) What was the average score after one year? 6863267978 (0) After how many months would it take for it to predict that the average dropped to 77? (Assume that the the model could continue past two years, if necessary)