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Háblame de las lenguas de España y cómo contribuyen a la identidad española

En España existen algunas lenguas diferentes, no solo el castellano. El catalán, de Cataluña y las islas baleares, es bien conocido por la gente fuera de España, también el euskera, idioma de los vascos.<...

Answered by Charlie M. • Spanish tutor

3293 Views

A rocket travels with constant velocity in a straight line in deep space. A ball is thrown from the back to the front (ie from the thrusters to the nose). Describe the path of the ball. Describe the path if the rocket were accelerating along this line.

Consider first what happens when the rocket travels with constant velocity. Constant velocity implies that there are balanced forces (or indeed no forces) acting on the rocket. This is Newtons 1st Law. We...

Answered by Sam W. • Physics tutor

5251 Views

Express 3cos(theta) + 5sin(theta) in the form Rcos(theta - alpha) where R and alpha are constants, R>0 and 0<alpha<90. Give the exact value of R and the value of alpha to 2dp.

Write out identity:

Rcos(theta - alpha) = Rcos(theta)cos(alpha) + Rsin(theta)sin(alpha) from formula booklet

Write out in form of question so it's easier to compare:

3cos(theta) + 5si...

Answered by Olivia S. • Maths tutor

15028 Views

What is the difference between a Bronsted Lowry acid and a Lewis Acid?

In chemistry there are two distinct theories to explain acid-base reactions; the Bronsted-Lowry and Lewis acid-base theories. The Bronsted-Lowry theory talks about removal or transfer of ...

Answered by Michael E. • Chemistry tutor

44796 Views

how to write down the differential equation from a word problem, involving rate of change.

Read the word problem more than once to make sure you fully understand what is being asked and write down the variables involved. Then try to write down all the derivatives in terms of each other, using t...

Answered by Christoforos G. • Maths tutor

3258 Views