Find each sum or difference. round to the place value of the less precise measurement.

2.13 m + 8.6 m

a. 6.47
b. 10.73
c. 10.7

proper answers, .

C: 10.7

Step-by-step explanation:

The sum is : 2.13 m + 8.6 m = 10.73 m

The difference is: 8.60 m  - 2.13 m =6.47

The precise sum is 10.73 m, bur after rounding to the place value of less precise measurement, we get 10.7 m. This means that the result (rounded) is not as close as the one found in the sum.

-14

step-by-step explanation:

2x2 – 2(x+4)

=2x2-2（5+4）

=4-2×9

=4-18

=-14

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58