Mi madre es muy (1) (blank) (trabajador / rubio): es artista y también ense? a en una universidad. a los estudiantes les gusta mi madre porque es una profesora (2) (blank) (bueno / antipático), pero ella da (gives) exámenes muy (3) (blank) (bonito / difícil). este semestre ense? a dos clases de arte

The right writing of the adjectives in each case is:

- Mi madre es muy trabajadora: es artista y también enseña en una universidad. A los estudiantes les gusta mi madre porque es una profesora buena, pero ella da exámenes muy difíciles. Este semestre enseña dos clases de arte.

Explanation:

The translation of the paragraph is:

- My mother is a hard worker: she is an artist and also teaches at a university. The students like my mother because she is a good teacher, but she gives very difficult exams. This semester teaches two art classes.

Although in English the adjectives are always singular and do not undergo changes regardless of the gender of the noun, in Spanish both the gender and the number of the noun must be taken into account in order to use the same adjective form, to identify whether the adjective used is correct or not first you must verify to what gender and number each one belongs:

As the first and second referred to the mother, singular adjectives are used and whose gender is female or both, meanwhile the third adjective is used for a plural and male noun "exámenes".

b.

explanation:

just because.

well, the b sentence is the only one that has sense.