Which statement about images is correct? a) a virtual image cannot be formed on a screen. b) a virtual image cannot be viewed by the unaided eye. c) a virtual image cannot be photographed. d) mirrors always produce real images.

Shown below is the start of a coding region within the fist exon of a gene. 5'--3' 3'--5' how many cas9 pam sequences are present?

Assume that there is a 4% rate of disk drive failure in a year. a. if all your computer data is stored on a hard disk drive with a copy stored on a second hard disk drive, what is the probability that during a year, you can avoid catastrophe with at least one working drive? b. if copies of all your computer data are stored on three independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?

Consider the following statements: struct nametype{string first; string last; }; struct coursetype{string name; int callnum; int credits; char grade; }; struct studenttype{nametype name; double gpa; coursetype course; }; studenttype student; studenttype classlist[100]; coursetype course; nametype name; mark the following statements as valid or invalid. if a statement is invalid, explain why. a.) student. course. callnum = "csc230"; b.) cin > > student. name; c.) classlist[0] = name; d.) classlist[1].gpa = 3.45; e.) name = classlist[15].name; f.) student. name = name; g.) cout < < classlist[10] < < endl; h.) for (int j = 0; j < 100; j++)classlist[j].name = name; i.) classlist. course. credits = 3; j.) course = studenttype. course;