Which statements about the cycle of weathering erosion and deposition are true? Check all that apply

Chalk is an ionic compound. which is a property of all ionic compounds that makes chalkboard? particularly useful for writing on a a high melting point hardness and brittleness inability to dissolve in water a multicolored appearance

Why does competiton happen? a: different organisms have different needsb: there are limited resources in an ecosystemc: there are no predators in an ecosystemd: organisms do not need the same resources (i think it's b but i'm not sure)

When designing a science presentation, look for credible sources. science doesn’t show bias, but humans do. avoid sites and articles that provide facts without citing proper scientific evidence. you must be able to identify reliable sites so that the data in your presentation is credible. use sources that end in .gov, such as cdc. gov. these government sites are reliable sources. you can also use sites ending in .edu. they are usually trustworthy, but sometimes students, not scientists, write content for .edu websites. always identify the source’s author before proceeding. some .org and .com sites are credible, but it’s important to verify their authenticity. when reviewing a source, ask these questions: who is the author? is this person an hiv or aids expert? what is the document’s purpose? does the document state facts that scientists can prove with evidence? are there opinions in the document? how old is the document? do other credible sources support the statements in the document? search for credible websites and note the information they contain. write down two sources that you will use for your presentation, and cite them using modern language association (mla) citation methods.