Answer:
8
Step-by-step explanation:
0) the basic formula is: L=v*t, where L - distance, v - speed/velocity; t - time;
1) if the person's speed in still water is 'v' and the speed of water is 5 (according to the condition), then the upstream speed is 'v-5' and the downstream speed is 'v+5';
2) according to the condition the upstream time and the downstream time are the same, it means t₁=t₂=t, where t₁=upstream time and t₂=downstream time;
3) according to the items above it is possible to make up the equation of the upstream travel: t(v-5)=3; ⇒ t=3/(v-5);
4) according to the items above it is possible to make up the equation of the downstream travel: t(v+5)=13; ⇒ t=13/(v+5);
5) if t=3/(v-5) and t=13/(v+5), then

Answer:
x = 30°
Step-by-step explanation:
The arcsin (inverse sine) function can be used. Be sure to set your calculator to degrees mode.
sin(x) = 1/2
arcsin(sin(x)) = arcsin(1/2)
x = arcsin(1/2)
x = 30°
X = x4
And
Y = x2
Because of the fact the cows have 4 legs and chickens have 2