@problem@
	@problemtype@
		essay
	@;problemtype@
	@name@
		tutorial_21_essay_questions
	@endname@
	@preamble@
		firstlaw = randbool()
		if firstlaw:
			numbertext = "first"
			correctanswer = "answer1"
		else:
			numbertext = "second"
			correctanswer = "answer2"
	@;preamble@
	@answer@
		@label@answer1@;label@
		If the net force acting on a body is zero, then the body does not change its velocity.
	@;answer@
	@answer@
		@label@answer2@;label@
		The temporal rate of change of momentum is directly proportional to the applied force.
	@;answer@
	@content@
		If the answer to a question can be typed into a (larger) text field, but not automatically graded by comparing it to a given string, then the 'essay' problem type might be a suitable choice.
		@pb;@
		Any such problem must contain exactly one call to the 'essay' function in order to specify the amount of given points as well as some additional options, including the editor type and the size of the text input field. If multiple 'answer' blocks are specified, the correct answer for the current case (which might depend on some random values generated in the preamble) can also be selected by its label.
		@pb;@
		It is also possible to provide the option to upload a solution file if the answer proves to extensive to be typed in or if, for example, mathematical formulae are required. A correct answer can be specified as well, which is shown in the exam feedback and accessible during grading.
		@pb;@
		@hr;@
		@pb;@
		What is the @numbertext@ law of Newtonian mechanics?
		@essay(20, answer=correctanswer, editor=HTML, lines=14, upload=False)@
	@;content@
@;problem@