Answer:
cos(400)
Step-by-step explanation:
Useful things:
Cofunction identity: sin(x)=cos(90-x)
Sine and cosine have period of 360 degrees.
So sin(50)=cos(40) by cofunction identity.
Since cosine has period of 360 degrees then cos(40)=cos(360+40).
That simplifies to cos(400).
Answer:
- <em>0.75</em><em> liters of 5% hydrochloric acid solution </em>
- <em>0.25</em><em> liters of 45% hydrochloric acid solution.</em>
Step-by-step explanation:
Let us assume that, x liters of the 5% hydrochloric acid and y liters of the 45% hydrochloric acid solutions are combined.
As Rajan need total of 1 liter of solution, so
i.e
--------------------1
As Rajan needs 5% hydrochloric acid and 45% hydrochloric acid to make a 1 liter batch of 15% hydrochloric acid, hence acid content of the mixture of two acids will be same as of the final one, so

i.e
-------------2
Putting value of x from equation 1 in equation 2,





Putting the value of y in equation 1,

Therefore, Rajan must use 0.75 liters of 5% hydrochloric acid solution and 0.25 liters of 45% hydrochloric acid solution.
Joe has a 1/2 probability of pulling a blue marble and 1/10 probability of pulling a red marble. 5/10+1/10= 6/10
6/10=3/5 there’s a 3/5 probability of pulling a blue than red marble
(i’m not sure if i completely understood i’m am very sorry if it’s wrong.)
the picture has bad quality, please send this question with better picture so i can answer all of them
Answer:

Step-by-step explanation:
The 10 represents the speed traveling downsteam while the 3 represents speed upstream. Downstream you have the help of the current, so it would be x + 2, upstream you are working against the current so it would be x - 2.