Answer:35.2 ft
Explanation:
Given
height of stick =4 ft
shadow length =2.8 ft
Angle of elevation of sun is

let the height of tree be h
as
will remain same thus


h=35.2 ft
Answer:
hi there!
the correct answer to this question is: 6.67 mph
Explanation:
you convert minutes to hours
10 miles * 60 mins / 90 mins
That's a weird graph, but judging from the units the acceleration is the slope of the graph.
a = (0.8 - 0.3)/(0.16 - 0.055) = 4.76 m/s²
Let's break the question into two parts:
1) The force needed in Ramp scenario.
2) The effort force needed in the lever scenario.
1. Ramp Scenario: In an incline, the only component of cart's weight(
mg) that is in the direction of motion is
. Therefore the effort force in this case must be equal or greater than
.
Now we need to find

.

is the angle between the incline of the ramp and the ground.
Since the height is
5m and the length of the ramp is
8m, 
would be
5/8 or 0.625. Now that you have

, mutiple it with
mg.
=> m*g*

= 20 * 10 * 5 / 8. (Taking g = 10 m/s² for simplicity) = 125N
Therefore, the minimum Effort force you would require in this case is
125N.
2. Lever Scenario:
Just apply "moment action" in this case, which is:


= ?

= mg = 20 * 10 = 200N

= 10m

= 1m
Plug-in the values in the above equation:

= 200/10=
20NAs 20N << 125N, the best choice is to use lever.
It will provide a clear picture of current system functions before any modifications or improvements are made is a benefit if they use the four-model approach.
<u>Option: D</u>
<u>Explanation:</u>
The four model approach is followed by number of analyst which showcase that they construct the physical and logical model of both current and new system. The most important advantage of such approach is it portrays transparent image of ongoing system, before one apply any modification or variation. This is necessary because the flaws which generated earlier in system may affect the SDLC phases and outcome of such process may result into unsatisfied user by paying additional cost. This can be avoided by taking additional steps which make it worth it. The major disadvantage of such approach is the added time and cost of constructing model in both current system.