Answer:
Diameter of riser =6.02 mm
Explanation:
Given that
Dimensions of rectangular plate is 200mm x 100mm x 20mm.
Volume of rectangle V= 200 x 100 x 20 
Surface area of rectangle A
A=2(200 x 100+100 x 20 +20 x 200)
So V/A=7.69
We know that
Solidification times given as
-----1
Lets take diameter of riser is d
Given that riser is in spherical shape so V/A=d/6
And
Time for solidification of rectangle is 3.5 min then time for solidificartion of riser is 4.2 min.
Lets take 

Now from equation 1

So by solving this d=6.02 mm
So the diameter of riser is 6.02 mm.
Answer:
In this era, Sun Ra was among the first of any musicians to make extensive and pioneering use of synthesizers and other various electronic keyboards; he was given a prototype Minimoog by its inventor, Robert Moog.
Explanation:
Answer:
Solar engineers plan, design, and implement solar energy projects. They may manage anything from large-scale municipal projects to home rooftop installations. He or she may also oversee or manage implementation of the plan. Solar engineers may also need to report on the efficiency, cost, and safety of the project.
Answer:
V = 125.7m/min
Explanation:
Given:
L = 400 mm ≈ 0.4m
D = 150 mm ≈ 0.15m
T = 5 minutes
F = 0.30mm ≈ 0.0003m
To calculate the cutting speed, let's use the formula :

We are to find the speed, V. Let's make it the subject.

Substituting values we have:

V = 125.68 m/min ≈ 125.7 m/min
Therefore, V = 125.7m/min
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