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Qui or Que?

It can be tricky to understand when to use each of these relative pronouns. But if we break it down it is actually quite simple! Qui is used as the subject of the clause, (ie. the person/thing doing the verb...
RT
Answered by Rebecca T. • French tutor
3948 Views

How does the reactivity of group 2 elements change down the group, and what is the cause of this trend?

Each row on the periodic table represents a new energy level/electron shell. So as you go down the group there are more energy levels, increasing the atomic radius. The first electron to react will be on the...
RR
Answered by Ruth R. • Chemistry tutor
53978 Views

Solve the simultaneous equations 4x + 7y = 1 and 3x +10y = 15.

There are two main ways of solving this equation, substitution and elimination, here we go through the susbtitution method. This involves rearranging one of the equations to get one of the variables in terms...
LC
Answered by Luke C. • Maths tutor
17492 Views

Why does lowering the control rods in a nuclear reactor reduce the amount of energy released each second from the nuclear fuel?

The boron control rods absorb slow-moving neutrons (thermal neutrons), which means that there are less available neutrons in the reactor. Since nuclear fission requires a collison between a neutron and a ura...
LC
Answered by Luke C. • Physics tutor
16360 Views

A capacitor discharge circuit of time constant 45ms includes a capacitor and resistor. The capacitor has a capacitance of 18µF What is the resistance of the resistor?

This question is in one of the CIE Physics Pre-U sample papers, and if you know the definition of the time constant for a capacitor circuit (=RC), its very easy, however even if you didnt it canbe derived fa...
SC
Answered by Sam C. • Physics tutor
6126 Views