Andrew had $250 in his savings account. he then deposits the same amount of money each week for 6 weeks. he deposits twice that amount each week for another 4 weeks. if d is the amount of money andrew deposits each of the first 6 weeks, which expression represents how much money he has in his account after 10 weeks?
a) 250 + d + 4(2d)
b) 250 - d + 4(2d)
c) 250 + 6d + 4(2d)
d) 250 - 6d + 4(2d)

The investigating team suspected that there were differences in the cost of repairing cars in workshop i and workshop ii. the investigating team suspected that the costs raised by workshop i were greater than workshop ii. for that they tested the repair of 15 cars in each workshop to see the cost of repairs. the decision of the right hypothesis to prove the suspicion above is a. h0 : μ1- μ2­ = 0; ha : μ1- μ2­ ≠ 0 b. h0 : μ1- μ2 ≥ 0; ha : μ1- μ2 < 0 c. h0 : μd ≥ 0; ha : μd < 0 with μd = μ2- μ1 d. h0 : μd = 0; ha : μd ≠ 0 with μd = μ2- μ1 e. h0 : μ1- μ2 = 0; ha : μ1- μ2 ≥ 0