Can someone please explain what I have to do​

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?

1.3.25 question suppose 40​% of all voters voted for a particular candidate. to simulate exit polls regarding whether or not voters voted for this​ candidate, five random samples of size 1010 and five random samples of size 10001000 have been generated using technology using a population proportion of 0.400.40​, with the accompanying results. complete parts a through c below. click the icon to view the simulation results. a. observe how the sample proportions of successes vary around 0.400.40. simulation compared to sample prop simulation compared to sample prop 1 ▾ 6 ▾ greater than 0.40 less than 0.40 equal to 0.40 2 ▾ less than 0.40 greater than 0.40 equal to 0.40 7 ▾ greater than 0.40 less than 0.40 equal to 0.40 3 ▾ greater than 0.40 less than 0.40 equal to 0.40 8 ▾ equal to 0.40 greater than 0.40 less than 0.40 4 ▾ greater than 0.40 equal to 0.40 less than 0.40 9 ▾ less than 0.40 greater than 0.40 equal to 0.40 5 ▾ equal to 0.40 less than 0.40 greater than 0.40 10 ▾ equal to 0.40 greater than 0.40 less than 0.40 click to select your answer(s) and then click check answer. 2 parts remaining clear all check answer

Bocephus has a bag full of nickels and dimes. if there are 3 times as many dimes as nickels, and he has $\$36.05$ in his bag, how many nickels does he have?