The density of the block will be "7.11 gm/cm³". A further explanation is provided below.
Given values are:
Density of iron,
Mass of block of metal,
Volume of block,
By using the formula,
→ 
then,
→ The density of block will be:
= 
= 
= 
Learn more:
brainly.com/question/10804879
C.
This is because the number of products is greater than the number of reactants.
Answer:
1. Mixture
2. Compound
3. Compound
4. Element
Explanation:
Number 1 shows two completely different types of compounds in the same space, so it is a mixture.
Numbers 2 and 3 are compounds because there aren't different types compounds as in Number 1, but the same compound repeated. 2 is a compound because while all of the circles are the same element, they are connected. O2 for example, oxygen, is a compound.
Number 4, finally, is all of the same substance, non-connected, so it shows an element.
Brainliest, please :) (Trying to become a genius so that I can continue helping more people)