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What's the difference between the passé composé and imperfect tense?

That's a great question, and one that we, as non-native French speakers, ask quite a lot. The most important thing to remember about the imperfect tense is that it is not perfect. And it's not perfect becaus...
KB
Answered by Kristian B. • French tutor
2185 Views

What's the difference between PED, PES, YED, and XED?

PED stands for Price Elasticity of Demand. It refers to the percentage change of quantity demanded (Qd) of a product as a result of a change in price (P) of that product. It is calculated by dividing the per...
JD
Answered by Joshua D. • Economics tutor
38429 Views

Derive the mgh approximation for gravitational potential energy.

Newton's law of gravitation -> GPE = GMm/r - GMm/(r+h)GPE = GMm(1/r - 1/(r+h))GPE = GMm(h)/(r(r+h))r >> h -> GPE ~ (m)(GM/r^2)h = mgh
IS
Answered by Inigo S. • PAT tutor
2685 Views

How unified was Italy in the period 1871-1914?

By 1871 Italy had come into being as a legally unified country. Disparate states and kingdoms were brought together under one unified legislative and executive body. This question examines the extent to whic...
Answered by • History tutor
4239 Views

An object is let in free fall from a platform 20m high above Earth's surface. Describe the event in terms of energy and thus determine the speed of the object when it hits ground. Air resistance is negligible and gravitational acceleration is constant.

When the object is at rest on the platform it has no kinetic energy, but only potential energy. The potential energy is m g h where m is the mass of the object, g the gravitational acceleration and h the hei...
CA
2743 Views