An ion must cross the cell membrane through active transport instead of passive when the ion
a. negatively charged
b. carried across by a protein
c. going against the concentrate ingredient
d. to small to move independently

the statement is true

lunar landing mission. apollo 11 was the first manned mission to land on the moon. the first steps by humans on another planetary body were taken by neil armstrong and buzz aldrin on july 20, 1969. the astronauts also returned to earth the first samples from another planetary body.

explanation:

atp is used for energy.

he movement of air through earth's or any planet's atmosphere is called wind, and the main cause of earth's winds is uneven heating by the sun. this uneven heating causes changes of atmospheric pressure, and winds blow from regions with high pressure to those with low pressure.

i hope this : )