Answer:
A ≈ 40.3 cm²
Step-by-step explanation:
The area of right Δ ACD is calculated as
A = 
bh ( b is the base and h the perpendicular height )
Here A = 50.5, b = CD and h = AC , then
× 14 × AC = 50.5
7 AC = 50.5 ( divide both sides by 7 )
AC ≈ 7.214
The area of Δ ABC is calculated as
A = × BC × AC × sin36°
= 0.5 × 19 × 7.214 × sin36°
≈ 40.3 cm² ( to 3 sf )
Answer:
a) 
, b) 
, c) 
, d) 
Step-by-step explanation:
a) Let assume an initial mass m decaying at a constant rate k throughout time, the differential equation is:
b) The general solution is found after separating variables and integrating each sides:
Where 
is the time constant and 
c) The time constant is:
The particular solution of the differential equation is:
d) The amount of radium after 300 years is:
Answer:
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay (α-decay), beta decay (β-decay), and gamma decay (γ-decay), all of which involve emitting one or more particles. The weak force is the mechanism that is responsible for beta decay, while the other two are governed by the electromagnetic and strong forces.[1]
Answers:
1) 3/8 + 3/6 = 7/8
3/8 + 3/6
Simplify
3/4 + 1/2
Transform the expression
3 + 4/8
Calculate
=7/8
_____________
2) 5/9 + 1/3 = 8/9
5/9 + 1/3
Transform the expression
5 + 3/9
Calculate
= 8/9
_____________
3) 5/12 + 7/8 = 31/24
5/12 + 7/8
Transform the expression
10 + 21/24
Calculate
= 31/24
_____________
4) 7/9 - 1/6 = 11/18
7/9 - 1/6
Transform the expression
14 - 3/18
Calculate
= 11/18
_____________
5) 4 2/5 + 2 1/5 = 33/5
4 2/5 + 2 1/5
Convert the number
22/5 + 11/5
Calculate
22 + 11/5
Calculate
= 33/5
_____________
6) 5 3/8 + 2 7/8 = 33/4
5 3/8 + 2 7/8
Convert the number
43/8 + 23/8
Calculate
43 + 23/8
Calculate
= 66/8
