Mary is planning to buy a mobile phone that costs $500. a salesperson at the store informs her about four different installment plans that she

can choose from.

plan a: a down payment of $50 and monthly payments of $40 for 12 months

plan b: a down payment of $100 and monthly payments of $80 for 6 months

plan c: no down payment and monthly payments of $60 for 12 months

plan d: no down payment and monthly payments of $100 for 6 months

The answer is A

Explanation:

The installment plan she will probably choose is a down payment of $50 and monthly payments of $40 for 12 months.

In the a real scenario, multiplying the installment amount of $40 with the total month of 12 then adding it answer with the down payment of $50 should arrive at the cost of $500 of the phone but it doesn't. However, the option A, has the figure closet to the initial cost of $500.

The cost by choosing the option A is $530 so it is assumed that the $30 extra is the interest attached to the elongated period of payment.

b) a state law could be declared illegal if it contradicted the constitution.

explanation:

the conflict of this case originated when james w. mcculloch, a cashier of the baltimore branch of the second bank of the united states that the congress had chartered in 1816, refused to pay a tax imposed by the maryland state.

in the case, the state of maryland appealed that the establishment of a second bank was unconstitutional since the constitution didn't say anything about granting that power to congress. however, the case determined that even if such right wasn't specifically stated in the constitution, it was part of the "implied powers" of the government enunciated in article i, section 8.

the case also eliminated maryland's legislation to impose taxes to a national bank, asserting that even though the states retained the power of taxation, the constitution's laws are supreme and can not be controlled by the states, therefore, if a state law contradicts the constitution, it should be declared illegal.

explanation:

a. the astrolabe could determine the correct latitudinal location of the ship