Answer:
The reactivity of metal is determined by the reactivity series. ... The metal which easily displaced aluminium will lie above in the series but that same element cannot displace sodium, so it will lie below in the series. Hence, from the series, we conclude that the unknown metal could be calcium or magnesium.
Explanation:
Hope this helps! :)
A. new ocean ridges and seafloor
Answer:
c. contraction
Explanation:
Heating will cause substances to expand, or change their state (like solid to liquid) or it may be a chemical reaction.
H ( hydrogen ) is the answer I believe.
Answer:

Explanation:
Hello,
Based on the acting force that is applied horizontally, one can propose the following equation based on Newton's laws:

Nevertheless, since we've got a angled force, it becomes:

In this case,
accounts for the formed angle, so the horizontal acceleration turns out into:

Best regads.