Calculate the molarity of a solution made by adding 28.2 mL of concentrated ammonia (28.0 % by mass, density 0.880 g/mL) to some water in a volumetric flask, then adding water to the mark to make exactly 500 mL of solution. (It is important to add concentrated acid or base to ...
A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0° above the horizontal. How long is she in the air before returning to Earth? (g = 9.81 m/s2)
A rancher wants to build a rectangular pen with an area of 180 . Let W be the width of the pen and L be the length of the pen. a) Find an equation for the perimeter P in terms of W and L . b) Use the given area to write an equation that relates W and L . c) Find the pen dimens...
What is (6.91 x 10-2 power) + (2.4 x 10-3 power) ? Express your answer in scientific notation.
. A package sitting on a shelf is knocked off. The velocity of the box just before it hits the floor is 8.5 m/s. Calculate the height of the shelf using; A displacement/velocity/acceleration equation Conservation of energy and hence show that these two methods produce the same...
A particular task exposes the operator to alpha radiation at an average dose of 200 ìGy each time the task is performed. If the company needs the task performed once per day over a 250-day working year and the maximum occupational dose limit is 20mSv per year, how many ...
This is an example question which I have the answer to but can not seem to get the same answer through my workings, any help with the equation would be great. A particular task exposes the operator to alpha radiation at an average dose of 200 ìGy each time the task is p...
Emma is 5 years older than 6 times beth's age. If Emma is 29 years old how old is Beth?
check my work on derivatives
Can someone check my work? So, I took the derivative of (1-x^2)/((1+x^2)^2) I used the quotient rule ((2x((1+x^2)^2)-2((1+x^2)^2)(2x)(1-x^2))) / ((1+x^2)^4) Then I simplified it (2x+2x^2 - 4x((1+x^2)^2)(1-x^2)) /((1+x^2)^4) Then I simplified by factoring out some numbers 2x(x^...
A motorist travelling at 82 km/hr is being chased by a police car at 121 km/hr. If the police car starts from 4.0 km back, how long does it take to catch the motorist? Leave time in hours.