Answer:
a) 90°
b) (d) The angle at the circumference in a semicircle is a right angle
Step-by-step explanation:
An inscribed angle has half the measure of the arc it subtends.
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Angle ABC is inscribed in a semicircle and subtends an arc of 180°, so has a measure of 180°/2 = 90°. Here, that observation is described by ...
The angle at the circumference in a semicircle is a right angle
1,700+.05(X-600)=2,100
-1700. -1700
.05(X-600)= 400
.05x-30 =400
+30=+30
.05x=. 430
Divided by .05
X=. 8,600
Answer:
=209.09 mg
Step-by-step explanation:
given: material= radium
half life= 1590 years
initial mass 
=500mg
we know that to calculate the amount left we use
= 
therefore
= 
=209.09058407921 mg
=209.09 mg amount left after 2000 years
The answer is 74. I'm 100% sure.
