Brainliest answer! an earth-like planet is 500 light years away. why is this an obstacle for a manned space mission?

a. the cost is too low
b. there is no oxygen in space
c. humans cannot live for 500 years
d. there are no plans to send a human

Identify the balanced chemical equation that represents a decomposition reaction. p4 + 3o2 ⟶ p2o3 2fe(oh)3 ⟶ 2feo3 + h2o cuso4 ⟶ cuo + 2so3 2fe(oh)3 ⟶ fe2o3 + 3h2o

Imagine that you have produced several versions of lactase, each of which differs from normal lactase by a single amino acid. describe a test that could indirectly determine which of the versions significantly alters the three-dimensional shape of the lactase protein.

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*