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The environment suffers because business has no ethics. Discuss

In some underdeveloped countries stricken with poverty, some companies take short cuts with the environment, such as by burning traditional fuels, using lead petrol and creating rubbish dumps in order to hel...
EJ
2848 Views

If an alpha particle (Z = 2) of kinetic energy 7 MeV is incident on a gold nucleus (Z = 79), what is its closest distance of approach?

In Rutherford Scattering, an incident particle will reach the closest distance of approach when it is on a collision course head on with the target nucleus. At the closest distance of approach, the alpha par...
RN
Answered by Robert N. • Physics tutor
5197 Views

When is the subjunctive mood used in French?

At A-level, students will be expected to be able to confidently use the subjunctive mood. With a student, I would first discuss with them what the already know about the subjunctive, or any phrases they alre...
LS
Answered by Laura S. • French tutor
2355 Views

Prove that ∑(1/(r^2 -1)) from r=2 to r=n is equal to (3n^2-n-2)/(4n(n+1)) for all natural numbers n>=2.

To prove the above statement we will be using proof by induction as this is the easiest way to prove that the statement holds for all natural numbers n>=2. Firstly, when proving by induction there are thr...
SP
4678 Views

There are 10 boys and 20 girls in a class. The mean mark in a test for all the class is 60. The mean mark for the girls is 54. Work out the mean mark for the boys.

First let us consider how we calculate the mean test mark in the first place, we add up the individual test marks of the entire class to give the total test mark then we divide by the number of students. Thi...
AD
Answered by Adam D. • Maths tutor
68060 Views