£28 call out charge +£16 for each half hour he spends on the repair .
what will the total cost be for a repair which takes one and half hours

$76 will be the total for one and a half ours for a repair.

Step-by-step explanation:

28 + 16hh

hh = half hour

1 and a half hours = 3 half hours

28 + 16(3)

28 + 48 = 76

50- 250 is correct i did that one too

step-by-step explanation:

(a) {a₁, a₁r, a₁r², … a₁rⁿ⁻¹, …}

(b) $59 398

step-by-step explanation:

(a) the annual sequence of profits

aₙ = a₁rⁿ⁻¹

the model for the sequence of profits is {a₁, a₁r, a₁r², … a₁rⁿ⁻¹, …} .

(b) profit after 15 yr

  a₁ = $ 30 000

  r = 1.05

a₁₅ = 30 000 × 1.05¹⁴

a₁₅ = 30 000 × 1.979 93

a₁₅ = $59 398

the profit in year 15 will be $59 398.