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The Planisphere
A planisphere is a visual aid to astronomers and stargazers.
It consists of two disks: One displays all of the visible
constellations in the night sky, and the other covers the first
and contains a window that indicates the portion of the sky currently
visible. The second disk is then rotated to match the current date and
time. Planispheres come in a variety of sizes and types. The important
thing to remember is that you must have a planisphere that matches
the longitude of your stargazing location.

On the right is an online planisphere. It consists of two images laid on
top of one another. The top image is the viewing disk of the planisphere. The
bottom image contains the sky map. This planisphere is
automatically rotated for you, displaying the current date and time
and visible constellations for observers at a longitude of
40° North. To use a planisphere, hold directly overhead with
the arrow facing north as indicated on the viewing disk.

March 1, 2018 4:53 PM

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What is a scenario where records stored in a computer frequently need to be checked

Write a program that displays the following menu: geometry calculator 1. calculate the area of a circle 2. calculate the area of a rectangle 3. calculate the area of a triangle 4. quit enter your choice (1-4): if the user enters 1, the program should ask for the radius of the circle and then display its area. use the following formula: area = ď€(the square of r) use 3.14159 for ď€ and the radius of the circle for r. if the user enters 2, the program should ask for the length and width of the rectangle and then display the rectangle’s area. use the following formula: area = length * width if the user enters 3, the program should ask for the length of the triangle’s base and its height, and then display its area. use the following formula: area = base * height * .5 if the user enters 4, the program should end. input validation: display an error message if the user enters a number outside the range of 1 through 4 when selecting an item from the menu. do not accept negative values for the circle’s radius, the rectangle’s length or width, or the triangle’s base or height. note: if the user enters an improper menu choice (1-4), the program prints "the valid choices are 1 through 4. run the program again and select one of those." if the user enters a negative radius, the program prints "the radius can not be less than zero." if the user enters a negative value for height or base, the program prints "only enter positive values for base and height."