Question

Anwer the question I will mark as brainlist

Answer 1

weight is equal to
mass ×gravity
80×9.8=784N
weight on Mars =80×3.7=296N

Answer 2

Mass of astronaut =80KG
$weight = m \times g$
Then, Weight on earth is:
$or \: weight = 80 \times 9.8$
$or \: weight = 784N$
Now weight on mars is :
$weight =80 \times 3.7$
$weight =296N$