Answer
See answers.
Work Step by Step
a. The charge of a neutron is 0. The strangeness, the charm, the bottomness, and the topness are also zero. It has a baryon number of 1, so it contains 3 quarks.
$$n = udd$$
b. The antineutron is the neutron’s antiparticle.
$$\overline{n} = \overline{u}\overline{d}\overline{d}$$
c. The $\Lambda ^ 0$ has a strangeness of -1, so one of the quarks must be an s quark. It is classified as a baryon, so it contains 3 quarks. Finally, the charge, charm, bottomness, and the topness are zero.
$$\Lambda ^ 0 = uds$$
d. The $\overline{\Sigma}^0$ has a strangeness of +1, so one of the quarks must be an $\overline{s}$ quark. It is classified as a baryon, so it contains 3 quarks. Finally, the charge, charm, bottomness, and the topness are zero.
$$\overline{\Sigma}^0 = \overline{u}\overline{d}\overline{s}$$