Express the answers to the following calculations in scientific notation, using the correct number of significant figures. (a) 145.75 + (2.3 × 10−1) × 10 (b) 79,500 / (2.5 × 102) × 10 (c) (7.0 × 10−3) − (8.0 × 10−4) × 10 (d) (1.0 × 104) × (9.9 × 106) × 10

(a)

(b)

(c)

(d)

Step-by-step explanation:

Scientific notation is a way of writing a very large or a very small number in the product of a number between 0 to 9 and the exponent of 10.

Also, the product rule of exponent,

Given,

(a)

(b)

(c)

(d)

the distance between the school and her home is 3.6km.

12 mins = 0.2 hours = 1/5 hour

54 ÷ 3 = 18km per hour

1/5 of 18 = 3.6km per 12 mins