Answer:
1.25
Step-by-step explanation:
Answer:
The rock will take about 4.5 seconds to reach the river
Step-by-step explanation:
* lets study the situation of the rock
- The rock is dropped means the initial velocity is zero
- The motion is free fall under earth gravity
- The rock dropped from a bridge 320 feet above the river
- The equation of the pathway is h = -16t² + 320
- When the rock reach to the ground the height will be zero
* Now lets substitute h by zero in the equation to find t
∵ h = -16t² + 320
∵ h = 0
∴ 0 = -16t² + 320 ⇒ add 16t² to both sides
∴ 16t² = 320 ⇒ divide both sides by 16
∴ t² = 320/16 = 20
∴ t² = 20 ⇒ take √ for both sides
∴ t = √20 = 2√5 ≅ 4.5 seconds
* The rock will take about 4.5 seconds to reach the river
<u>Answer:</u>
Cost of sand = £150
Cost of bricks = £157.5
Cost of cement = £134
Total cost = £441.50
<u>Step-by-step explanation:</u>
We are given that:
2 tonnes of sand is for £75.00 per tonne,
20 bags of cement are for £6.70 per bag,
350 bricks at 45p each,
So, 2 tonnes of sand at £75.00 per tonne = 2 * £75.00 = £150.00
20 bags of cement at £6.70 per bag = 20 * £6.70 = £134.00
350 bricks at 45p each = 350 * £0.45 = £157.50
Therefore, the total cost of all the materials = £150 + £134 + £157.5 = £441.50
Answer:
Step-by-step explanation:
hello :
sin x + 2 sin x cosx = 0 equivalent to : sinx(1+2cosx) =0
sinx=0 means : general solution is : x= kπ....k in Z
1+2cosx=0 means : cosx= -1/2 general solution is : x= ±π/6+kπ...k in Z
Answer:
4 miles.
Step-by-step explanation:
3.50 ×4=11.50.