Number one is really easy just set it up in proportions. 420 over x and 7 hours over 24 cause you know there 24 hours in a day and then cross division and simplify. I think.
For this case, the first thing you should know is that by definition, the vertical angles are congruent.
We have then:
∠1 and ∠2 are vertical angles.
Therefore, by definition:
∠1 = ∠2
On the other hand we have:
∠2 has a measure of 31 °.
Thus:
∠1 = ∠2 = 31 °
Answer:
the measure of ∠1 is:
∠1 = 31 °
a) Area of rhombus = ½ * (diagonal1)*(diagonal 2)
Let diagonal (D2 )= longer diagonal = 15 and diagonal (D1) = shorter diagonal
90 = ½ (D1)*15
90 = 7.5 D1
Now divide both side by 7.5
90/7.5 = d1
D1= 12 units.
b) Area of rhombus = ½ * (diagonal1)*(diagonal 2)
Let the ratio be 
Diagonal 1= 
Diagonal 2= 
147 = ½ * 
Multiply both side by 2
294 = 
294 = 6
Divide both side by 6
294/6 = 6
/6
49 = 
= 7 unit
3
multiply by 4
12
add 12
24
divide by 2
12
subtract 6
6
number 6 : 6(4) = 24... + 12 = 36...36/2 = 18.....- 6 = 12
number 8 : 8(4) = 32....+ 12 = 44...44/2 = 22....- 6 = 16
number 12: 12(4) = 48....+ 12 = 60...60/2 = 30....-6 = 24
well...by following these steps, it appears the original number doubles as a result.