Part d: float check string has a method s. isdigit() that returns true if string s contains only digits and false otherwise, i. e. s is a string that represents an integer. write a function named float_check that takes one parameter that is a string and returns true if the string represents a float and false otherwise. for the purpose of this function we define a float to be a string of digits that has at most one decimal point. note that under this definition an integer argument will return true. remember “edge cases” such as “45.” or “.45”; both should return true. for example: float_check('1234') returns true float_check('123.45') returns true float_check('123.45.67') returns false float_check('34e46') returns false float_check('.45') returns true float_check('45.') returns true float_check('45..') returns false

5.a fishing rod is formed from a composite material of 0.5 kg of glass fibers embedded in a matrix of 0.5 kg of epoxy resin. the glass fibers are assumed to be long, continuous and unidirectional. to achieve a greater stiffness it is proposed to use a different composite that is comprised of long continuous carbon fibers that will be embedded in a matrix of 0.5 kg of epoxy resin. if the modulus of elasticity of the carbon fiber composite is 10% greater than the elastic modulus of the glass fiber composite, estimate the mass of carbon fibers that will be used to make the carbon fiber composite. assume the applied tensile stress is parallel to the direction of the long axis of the fibers. the epoxy resin, glass fiber, and carbon fiber have an elastic modulus of 5, 86, and 350 gpa respectively and a density of 1100, 2500, and 1800 respectively.