To determine Kelly's weight in newtons when her mass is 70 kilograms, we can use the formula for weight. Weight (W) is calculated by multiplying mass (m) by the acceleration due to gravity (g). Mathematically, it is expressed as:
[tex]\[ W = m \times g \][/tex]
Given:
- Kelly's mass, [tex]\( m = 70 \)[/tex] kilograms
- The acceleration due to gravity, [tex]\( g = 9.8 \)[/tex] m/s[tex]\(^2\)[/tex]
Plugging these values into the formula, we get:
[tex]\[ W = 70 \times 9.8 \][/tex]
After performing the multiplication, the result is:
[tex]\[ W = 686.0 \text{ newtons} \][/tex]
Thus, the correct answer is [tex]\( A. 70 \times g \)[/tex].
