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How do waterfalls form?

Waterfalls form where a river is flowing over hard rock lying on soft rock. The soft rock is eroded faster, so there is a step in the river which deepens over time. It is eroded by hydraulic action and ab...

Answered by Dakota R. • Geography tutor

3392 Views

The roar of a tiger in a zoo can be heard by visitors at the entrance, even though the tiger can not be seen because there is a hill in the way. Name and explain this effect.

This effect is called diffraction. This occurs when waves spread over obstacles or through gaps.

Answered by Matilda C. • Physics tutor

2850 Views

Using answer to previous question state the coordinates of the minimum

From previous question y=2(x+2)²-1Minimum would be when (x+2)² is at it's smallest value, in this case when (x+2)=0 since any other value squared would be greater than 0. This occurs...

Answered by Matilda C. • Maths tutor

3216 Views

Express 2x^2 +8x +7 in the form A(x+B)^2 + C, where A, B and C are constants

2x²+8x+7=2(x²+4)+7=2((x+2)²-4)+7=2(x+2)²-8+7=2(x+2)²-1A=2, B=2, C=-1

Answered by Matilda C. • Maths tutor

9066 Views

How does a pregnancy test work?

1) The wick of the pregnancy test is socked in urine. 2) The test contains mobile monoclonal antibodies with small coloured beads attached to them. 3) These mobile monoclonal antibodies only bind t...

Answered by Lijun Z. • Biology tutor

20048 Views