A． Because walking on Mars will be easier than walking on the Moon.
B． Because there is more gravity on the Moon than on Mars.
C． Because walking quickly will be more difficult on Mars than on the Moon.
D． Because astronauts on Mars will require more oxygen than on the Moon.
A． They took short and quick steps.
B． They were pulled off the tread wheel.
C． They lost their balance.
D． They took longer and coordinated steps.
A． Martian spacesuits will have larger air tanks.
B． Martian spacesuits will be equipped with special weights.
C． Martian spacesuits will be more flexible.
D． Martian spacesuits will be less durable.