Legit only plz thanks

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

Aaron invested a total of $4,100, some in an account earning 8% simple interest, and the rest in an account earning 5% simple interest. how much did he invest in each account if after one year he earned $211 in interest? select one: a. $200 at 8%, $3,900 at 5% b. $3,200 at 8%, $900 at 5% c. $900 at 8%, $3,200 at 5% d. $3,900 at 8%, $200 at 5%

Griffin ordered a pair of sneakers online. he had a $22 credit that he applied toward the purchase, and then he used a credit card to pay for the rest of the cost. if the shoes cost $58, how much did griffin charge to his credit card when he bought the sneakers?