Can someone please tell me how to get rid of this top bar?

An atom's diameter is about 0.1 nanometer (1×10-9m), and a human hair is about 1×10-3m. how many times greater is a human hair than an atom's diameter? sorry pushed wronf button but this is math

Elements such as fonts colors visual structure graphics and the interface of a web page should complement each other to ensure blank

Apython programming question: assume s is a string of lower case characters. write a program that prints the number of times the string 'bob' occurs in s. for example, if s = 'azcbobobegghakl', then your program should print number of times bob occurs is: 2